Coating composition



Patented Apr. 9, 1935 UNlTED STATES signor to Sylvania No Drawing.

I COATING COMPOSITION Ralph T. K. Cornwell, Fredericksburg, Va., as-

Industrial Corporation,

Fredericksburg, Va., a corporation of Virginia Application November 2,1932,

Serial No. 640,899

r 16 Claims.

invention relates to moistureprooi compositions and has as a generalobject the'provision of novel compositions of matter adapted to be usedwith a solvent in the formation of z ransparent, non-greasy, non-tackyand moistureproof coatings, sheets, films, etc.

Another object of theinvention is to provide a lacquer or coatingcomposition comprising a lacquer base, a wax and a non-resinous agentwhich will increase the quantity of wax compatible in compositions ofthe type hereinafter referred to.

A specific object of the invention is to incorporate a blown oilymaterial with a coating composition comprising allacquer base and a waxwhereby novel and important properties are imparted to the compositionand to films or coatings formed therefrom.

It is a furtherspecific object of the invention to provide a novelwax-containing composition for the production of sheets, films orcoatings which, in addition to being transparent, moistureproof,non-tacky and non-greasy, shall be heat-scalable to such a degree as toenable contiguous surfaces coated therewith to .be autogenouslyheat-sealed at relatively low temperatures. r V e Other objects ofthe'invention will in part' be obvious and will in part appearhereinafter.

The invention accordingly comprises novel products possessing thecharacteristics, properties and the relation of constituents, allasexemplified in the following detailed disclosure and the scope of theapplicationof which will be indicatedin the claims. 7

As shown in my copending application-Serial No. 517,298, filed February20, 1931, nitrocellulose is compatible with only limited quantities ofwax. and :in general the addition of plasticizers decreases stillfurther the amount of wax which can be incorporated in nitrocelluloseand yet give rise to clear films. Heretofore, in order to incorporatemore than about 2% of wax-in a transparent cellulosic coating, such forexample as one containing nitrocellulose, a plasticizer and wax, ithasbeen deemedessential to employa gum or resin to render the waxcompatiblewiththe lacquer base. Prindle United States Patent-l,737,l87,'there is disclosed a coating composition for moistureproofingregen'erated'cellulose sheets comprising from 30 to parts ofnitrocellulose, *30 to 60 parts of gum, 2 to 6 parts of wax and-'5 to30parts of plasticizer. The disadvantages of varying-from theseingredients and proportions, andin partic- For instance; inthe Charchand ular the necessity for the use of the gum, is pointed out at lengthin this patent. l 7

As shown in my copending application Serial .No. 517,298, an excellentmoistureproofihg composition may be obtained using less than 2% of waxand eliminating entirely the gum or resin.

While the composition of the copending case is 4 useful for a widevariety of purposes, it is desir-' able for certain'applications to havea composition possessing a still higher moistureproofness withmaintained heat-sealability, and this is ac-' complished effectively andefliciently by the present invention by the use of blown oil.

In carrying .out the invention, I employ a composition comprisinggenerally a compatible mixture of lacquer base, a wax and a blown oil,and a plasticizer in cases where added flexibility is desired. I havefound thatthe use of a relatively small amount of blown oil enables meto By way of illustration but not by way of limitation, there are givenin the following table the several ingredients of a novel coatingcomposition, formulated in accordance with the present invention,(exclusive of solvents):

Lacquer base 50%-"l5% Plasticizer 25 457, Wax 0.5% 5% Blown oil .5%-- 5%The lacquer base comprises preferably nitrocellulose; however, it maycomprise anyother suitable cellulose derivative andforms a major part ofthe coating composition, as is well known" 7 to the art to which thisinvention appertain's."

Any suitable plasticizer or mixture of plasticizers may be used wheneverthe composition is to be formed into films or coating s where"increasedflexibility is required; Where good iheat se'alability is desired, theplasticizer-"should be "so constituted that the composition sealsreadil?at' moderate temperatures, say of the order ofto C. to make a'te'nacious, autogenousheat-seal of contiguous coated surfaces.;'.Ex

amples of preferred plasticizers are ethoxyeth'yl" y phthalate,-methoxyethyl phthalate, tripheny phosphate, and ben'zoate. 7

methyl, ethyl orf butylfbenz'oyl' Any suitable animaljminera l orvegetable na am m 55 may be used, but I prefer to use ahigh meltingpoint.

For the blown oil, I have found that either a blown or boiled oil(hereinafter referred to generally as blown oil), of animal or vegetableorigin may be employed, such as, for example,

'blown or boiled rapeseed, neats-foot, linseed,

constituents may be added if desired, without.

departing from the spirit of the invention.

When the amount of blown oil is greater than about 5% of the weight ofthe coating compo-' sition exclusive of the solvent, the film or coatingthus produced may be slightly oily and such 'oiliness increases withincrease in the quantity of blown oil used. Further, the properties ofmy improved coating composition appear to be best suited for autogenous;heat-sealing of contiguous surfaces coated therewith at temperatures inpractical use, when the quantity of blown oil does not substantiallyexceed 5%. The quantities of oil used should be adjusted with respect/cothe texture of the coated material.

By way of more specific illustration of improved moistureproofingcompositions embodying my novel ingredient, I mention the followingexamples in which all ingredients, except the solvents, are expressed byparts by weight:

Dibutyl phthalate Diethyl phlhalaie Tripheny] phosphate. Blown rapeseedoil.-.

Blown'neats-ioot oil. 3.5 Boiled linseed oil 3. 5 l. l 3. 1.

Paruflin A lacquer may be prepared by taking up about lorparts of one ofthe above compositions in about 150 parts of a suitable solvent such as,for ex ample, oneconsisting of 15%ethyl acetate, 15%

.butyl acetate and 70% toluene. This solution may then be applied as acoating and dried in a heated dryer in the usual way, or formed intosheets orfilms, etc. if desired.

These novel compositions may be'used in a number of arts, but areparticularly advantageous for moistureproofing wrappingmaterials onaccount 60,.

7 erably on each side, with a moistureproofing composition ofapproximately 1.5 ten thousandths of an inch total thickness prepared inaccordance with thepresent invention the resistance of the ,coatedfsheetto the diffusion of water vapor is atleast 5|] times asigreat astliat ofthe un'coated sheet of glycerinated regenerated cellulose when both aretested comparatively at ordinary temperatures up to 38 or 40 C. The termmois-v tureproof as used herein is intended to cover a compositionhaving such a moistureproofing value when so tested.

It will thus be seen that by means of the present invention there havebeen provided novel moistureproofing compositions having improved andtechnically important properties which may be economically and easilyprepared and used, and since certain changes may be made in theabovementioned products and different embodiments of the invention couldbe made without departing from the scope thereof, it is intended thatall 'matter contained in the above description shall be interpreted asillustrative and not in a limited sense. It is also to be understoodthat in said claims ingredients recited in the singular are intended toinclude compatible mixtures of such ingredients wherever the sensepermits.

Having described my invention, what I claim as new and desire to secure,by Letters Patent is:

1. A composition for preparing moistureproof, transparent, non-oily,non-tacky coatings or films, comprising a compatible mixture of acellulose derivative, up to about 5% of a wax and up to about 5% ofblown oil.

2. A composition for preparing flexible, moistureproof, transparent,non-oily, non-tacky and readily heat-sealable coatings or films,comprising a compatible mixture of a cellulose derivative, up to about5% of a wax, a'plasticizer, and up to about 5% of non-resinous waxsolvent consisting of blown oil.

3. A composition for preparing moistureprooi', transparent, non-oily,and non-tacky coatings or films, comprising a compatible mixture of acellulose derivative, up to about 5% of a wax, and

up to about 5% of blown rapeseed oil.-

4. A composition for preparing flexible, moistureproof, transparent,non-oily, non-tacky and readily heat-sealable coatings or films,comprising a compatible mixture of acellulose derivative,

up to about 5% of a wax, a plasticizer, and upto about 5% ofnon-resinous wax solvent con sisting of blown rapeseed oil.

5. A composition for preparing flexible. moistureprooi', transparent,non-oily, non-tacky and readily heat-scalable coatings or films,comprising a compatible mixture of a cellulose derivative in an amountof from'about 50% to 75%, a plasticizer in an amount of from about 25%to 45%,

a wax in an amount of from about 0.5% 'to 5%,

and a non-resinous wax solvent consisting of blown oil in an amount offrom about 0.5% to 5%. 6. A composition for preparing moistureproof,

blown oil, said wax being present in said composition in an amount offrom about 0.5% to V 4.5% and said oil being present in an amount justsufiicient to avoid wax blush in the. final.

coating or film.

7. A composition for preparing ilexiblepmois- V tureproof, transparent,non-oily, non-tackyand readily heat sealablecoatings or films,comprising a compatible mixture ofa cellulose deriva-,

tive, a wax, a plasticizer, and up to about 5% ofnon-resinous waxsolvent consisting of blown rapeseed oil, said wax being present in saidcomposition in an amount of from about 0.5% to 4.5% and said oil beingpresent inan amount just suflicient to avoid wax blush in the flnalcoating orfilm. 1

8. A composition for preparingmoistm'eproOiC; transparent, non-oily andnon-tacky coatings or' films, comprising a compatible mixture ofnitrocellulose, up to about 5% or a wax, and up to about 5% of blownrapeseed oil.

9. A composition for preparing flexible, moistureproof, transparent,non-oily, non-tacky and readily heat-scalable coatings or films,comprising a compatible mixture of nitrocellulose, up to about 5% of awax, a plasticizer, and up to about 5% oi. non-resinous wax solventconsisting of blown rapeseed oil.

10. A composition for preparing flexible, moistureproot, transparent,non-oily, non-tacky and readily heat-scalable coatings or fllms,comprising a compatible mixture of nitrocellulose in an amount of fromabout 50% to 75%, a plasticizerln an amount of from about 25% to a waxin an amount or from 0.5% to 5%, and a nonresinous wax solventconsisting of blown oil in an amount oi from about 0.5% to 5%.

11. A flexible, moistureproof, transparent, nonoily, non-tacky film,comprising a cellulose derivative, up to about 5% of a wax, and up toabout 5% of a blown oil.

12. A flexible, moistureproof, transparent, nonoily, non-tacky film,comprising a cellulose nitrate, up to about 5% of a wax, and up to about5% of a blown oil.

13. A flexible, moistureproof, transparent nonoily, non-tacky andreadily heat-scalable fllm,

comprising a cellulose derivative, a plasticizer, up to about 5% of awax, and up to about 5% or non-resinous wax solvent consisting of blownrapeseed oil.

14. A flexible, moistureproof, transparent, nonoily, non-tacky andreadily heat-sealable film, comprising a cellulose nitrate, up to about5% of a wax, a plasticizer, and up to about 5% of non-resinous waxsolvent consisting of blown 15. A flexible, moiatureproof, transparent,nonoily, non-tacky and readily heat-scalable fllm comprising a cellulosederivative, a plasticizer, a wax and a non-resinous wax solventconsisting of blown oil, said wax being present in said composition inan amount of from about 0.5% to 5% and said oil being present in anamount just suflicient to avoid wax blush in the final coating or fllm.

16. A flexible, moistureproof, transparent, nonoily, non-tacky andreadily heat-scalable film comprising a compatible mixture ofnitrocellulose in an amount of from about to a plasticizer in an amountof from about 25% to 45%, a wax in an amount of from about 0.5% to 5%,and a non-resinous wax solvent consisting of blown oil in an amount offrom about 0.5% to 5% RALPH T. K. CORNWELL.

